[PATCH AUTOSEL 4.14 30/34] leds: lp5523: fix a missing check of return value of lp55xx_read

Sasha Levin
2019-02-13T02:47:04Z

From: Kangjie Lu <kjlu@umn.edu>

[ Upstream commit 248b57015f35c94d4eae2fdd8c6febf5cd703900 ]

When lp55xx_read() fails, "status" is an uninitialized variable and thus
may contain random value; using it leads to undefined behaviors.

The fix inserts a check for the return value of lp55xx_read: if it
fails, returns with its error code.

Signed-off-by: Kangjie Lu <kjlu@umn.edu>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/leds/leds-lp5523.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/leds/leds-lp5523.c b/drivers/leds/leds-lp5523.c
index 924e50aefb00..13838d72e297 100644
--- a/drivers/leds/leds-lp5523.c
+++ b/drivers/leds/leds-lp5523.c
@@ -318,7 +318,9 @@ static int lp5523_init_program_engine(struct lp55xx_chip *chip)

/* Let the programs run for couple of ms and check the engine status */
usleep_range(3000, 6000);
- lp55xx_read(chip, LP5523_REG_STATUS, &status);
+ ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
+ if (ret)
+ return ret;
status &= LP5523_ENG_STATUS_MASK;

if (status != LP5523_ENG_STATUS_MASK) {
--
2.19.1